Phosphite (Phi) and phosphate (Pi) share the same root uptake system, but Phi acts as a biostimulant that modulates plant growth and disease resistance in a species‑ and Pi‑dependent manner. In Arabidopsis, Phi induces hypersensitive‑like cell death and enhances resistance to Plectosphaerella cucumerina, while in rice it counteracts Pi‑induced susceptibility to Magnaporthe oryzae and Fusarium fujikuroi, accompanied by extensive transcriptional reprogramming.
The study examined leaf pavement cell shape complexity across a natural European aspen (Populus tremula) population, using GWAS to pinpoint the transcription factor MYB305a as a regulator of cell geometry. Functional validation showed that MYB305a expression is induced by drought and contributes to shape simplification, with cell complexity negatively correlated with water-use efficiency and climatic variables of the genotypes' origin.
A genome‑wide association study of 187 bread wheat genotypes identified 812 significant loci linked to 25 spectral vegetation indices under rainfed drought conditions, revealing a major QTL hotspot on chromosome 2A that accounts for up to 20% of variance in greenness and pigment traits. Candidate gene analysis at this hotspot uncovered stress‑responsive genes, demonstrating that vegetation indices are heritable digital phenotypes useful for selection and genetic analysis of drought resilience.
The study genotyped 545 accessions from 17 Urochloa species using genome-wide SNP and SilicoDArT markers generated via DArTseq, revealing two major groups separating the brizantha complex from other wild species and identifying four phylogenetic clades. Population structure and admixture analyses highlighted distinct genetic clusters, extensive admixture in the cultivated brizantha complex, and high diversity with geographic structuring in wild apomictic species, informing conservation and breeding strategies.
The study examined how DNA methylation influences cold stress priming in Arabidopsis thaliana, revealing that primed plants exhibit distinct gene expression and methylation patterns compared to non-primed plants. DNA methylation mutants, especially met1 lacking CG methylation, showed altered cold memory and misregulation of the CBF gene cluster, indicating that methylation ensures transcriptional precision during stress recall.
The authors produced a chromosome‑scale genome assembly for an Australian finger lime (Citrus australasica) using long‑read sequencing, optical mapping, and a high‑density genetic map, resulting in nine pseudomolecules covering >97% of the genome. Resequencing of 132 Asian and Oceanian citrus accessions enabled high‑resolution SNP discovery and identification of species‑specific markers, revealing strong population structure and complex hybridization patterns that inform breeding and evolutionary studies.
Using a forward genetic screen of 284 Arabidopsis thaliana accessions, the study identified extensive natural variation in root endodermal suberin and pinpointed the previously unknown gene SUBER GENE1 (SBG1) as a key regulator. GWAS and protein interaction analyses revealed that SBG1 controls suberin deposition by binding type‑one protein phosphatases (TOPPs), with disruption of this interaction or TOPP loss‑of‑function altering suberin levels, linking the pathway to ABA signaling.
The study combined high-throughput image-based phenotyping with genome-wide association studies to uncover the genetic architecture of tolerance to the spittlebug Aeneolamia varia in 339 interspecific Urochloa hybrids. Six robust QTL were identified for plant damage traits, explaining up to 21.5% of variance, and candidate genes linked to hormone signaling, oxidative stress, and cell‑wall modification were highlighted, providing markers for breeding.
Scaling up orphan crop research: A global genetic perspective of cowpea (Vigna unguiculata) diversity from 10,617 accessions
Authors: Pearson, S. M., Hathorn, A., Sun, S., Cruickshank, A., Shatte, T. L., Munisse, P., Macharia, M., Conner, J., Koltunow, A. M. G., Vielle-Calzada, J. P., Ozias-Akins, P., Ishii, T., Dell Acqua, M., Norton, S., Tao, Y., Jordan, D., Mace, E.
The study performed the most extensive genetic diversity analysis of cowpea to date, genotyping 10,617 accessions from seven worldwide collections using genotyping-by-sequencing. It identified nine geographically associated genetic groups, revealed considerable redundancy across collections, and highlighted untapped diversity outside sub‑Saharan Africa, providing a foundation for more effective germplasm utilization and breeding.
The study investigates how the timing of the vegetative phase change (VPC) in Arabidopsis thaliana influences drought adaptation, revealing strong genotype-by-environment interactions that create stage-specific fitness tradeoffs. Genotypes from warmer, drier Iberian climates transition earlier, and genome-wide association mapping identifies loci linked to VPC timing and drought response, with several candidates validated using T‑DNA insertion lines.